Wrapping machine sheet selector



Dec. 10, 1968 J. D. CONTIv WRAPPING MACXINE SHEET SELECTOR Filed March 23, 1966 2 Sheetsheet l Dec. 10, 1968 J. D. CONTI WRAFPING MACHINE SHEET SELECTOR Filed March 23, 1966 2 Sheets-Sheet 2 United States Patent Oftice Patented Dec. 10, 1968 3,415,508 WRAPIING MACHINE SHEET SELECTOR John D. Conti, Elkins Park, Pa., assignor to FMC Corporation, Philadelphia, Pa., a corporation of Delaware Filed Mar. 23, 1966, Ser. No. 542,442 1 Claim. (Cl. 271-9) ABSTRACT F THE DISCLOSURE Article wrapping apparatus having suction means for delivering individual sheets of wrapping material from selected supply bins and into position for easy access by a wrapping operator.

The present invention relates to an apparatus for removing and delivering individual sheets from a large supply of sheets.

With various articles, such as meats, baked goods, vegetables and other food products, manual wrapping procedures are employed to insure adequately and attractively wrapped packages without waste of wrapping material. In such procedures, individual sheets of Wrapping material, which are best suited for the particular article to be Wrapped, are individually selected from a large assortment of stacked sheets which are made available to a wrapping operator. Not only are these sheets of wrapping material extremely thin, they generally exhibit a tendency to adhere or cling to each other, which is often aggravated by stacking, thus making sheet separation a tedious and time-consuming task for even a skilled article wrapping operator. Accordingly, the primary object of this invention is to provide a generally new or improved and more satisfactory apparatus for separating individual sheets of wrapping material from stacks of sheets.

Another object of this invention `is the provision of an apparatus which is adapted to remove individual sheets of wrapping material from a supply of stacked sheets of wrapping material and deliver the same into position for use by an article wrapping operator.

Still another object is to provide an improved apparatus in which ya large 'assortment of stacked sheets of wrapping material are made available and individually selected and positioned for use by an article wrapping operator.

Still further objects will appear from the following description.

These objects are accomplished in accordance with the present invention by an apparatus having gripping means which are adapted to engage with and remove individual sheets of wrapping material from a selected stack of sheets. Normally stacks of different wrapping mate rial are provided and are contained within individual bins which are adapted to be selectively moved into position for proper engagement by the gripping means.

The sheet gripping means includes lat least one and preferably a pair of suction heads which are capable of actually reaching into a selected bin, engaging and holding onto the topmost sheet of the stack of sheets contained within such bin, and then carry the engaged sheet toward a wrapping table and within the easy reach of an article wrapping operator. The suction heads are mounted so as to satisfactorily perform their intended function regardless of the height of the stack of sheets within any particular bin, and are capable of automatic and continuous operation, as where a series of individual sheets are to be removed from the same stack of sheets. Preferably a continuous vacuum is maintained on the suction heads so that portions of each sheet which is re moved from a selected bin are held away from a wrapping table or other structure for easy access by the operator.

The stacks of sheets which are contained within the bins may be of different sizes and/or of diEerent compositions to accommodate articles of varying sizes or character. However, for the sake of simplicity, the apparatus of the present invention is hereafter described as employed in manual wrapping of articles of different sizes with various size sheets, as for example of regenerated cellulose supplied as individual stacks and contained within separate bins.

In the drawing:

FIGURE 1 is a side view of the apparatus of the present invention;

FIGURE 2 ,is an end view of the apparatus shown in FIGURE l; and

FIGURE 3 is a top view of a portion of the apparatus shown in FIGURES l and 2.

With reference to the drawing, the apparatus of the present invention is supported by a rigid structure which includes a base plate 11, side walls 13 and a wrapping table 15 having an opening 17. A series of bins 19 are rigidly interconnected to each other in vertically spaced relationship by plates 21 and are supported by an elevator 23 for selective movement through the table opening 17. The bins 19 are intended to contain sheets of wrapping material of different sizes and each include upstanding walls 25, the front one of which is formed with a pair of spaced slots 27, for reasons as hereafter described.

The elevator 23 includes a platform 29, on which rest the series of bins 19, and at least one pair of links 31 and 33 which are pivoted to each other at 35 and to the base plate 11 and platform 29 at 37 and 39, respectively. The links 31 and 33 are turned about the pivot 35 by a conventional hydraulic lifting means which includes a cylinder 43 pivoted at 45 to a support 47 and a piston having a rod 49 pivoted at 51 near the free end of the link 33. A pump 53, having an operating switch 55 and flow reversing valve switch 57, is provided for delivering and discharging hydraulic uid to and from the opposite ends of the cylinder 43 through conduits 59.

Preferably, and as illustrated in FIGURE 2, two pairs of links 31 and 33 are employed, with each being actuated by separate hydraulic means which are supplied by the single pump 53. The two pairs of pivoted links are interconnected to each other by a rod 61 so as to move in unison and thereby insure smooth vertical movement of the elevator 23. Rollers 63 are provided at the ends of the rod 61 and `are guided along horizontal tracks formed by plates 65 and Z-shaped bars 67. In addition, rollers 69 are also provided at the free ends of the links 31 and ride along the underside of the platform 29 during elevator movement.

Once a bin 19 containing sheets of a desired size is at least approximately aligned with the table 15, individual sheets are selectively removed from such bin by a pair of suction heads 71 which are fixed to the uppermost ends of a pair of conduits 73. Sleeves 75 support the conduits 73 for vertical sliding movement and form a part of a carriage 77 which is adapted to be reciprocated toward and away from the bins 19. Rollers 79 project from the opposite sides of the carriage 77 and ride lalong horizontal tracks 81 which are fixed to the inside surfaces of the side walls 13.

A pair of levers 83 are pivoted at 85 to the side walls 13 and are connected by links 87 to the carriage 77. Tension springs 89 act on the levers 83 for maintaining their follower rolls 91 engaged with the peripheries of plate cams 93. A shaft 95 carries the cams 93 and is driven by a motor 97 through a chain 99 and sprockets 101 and 103. Operation of the motor 97 is controlled by a switch which is electrically connected to the motor by wires 107.

Vertical movement of the conduits 73 relative to the sleeve 75 is regulated by a pair of plate cams 109, which are also xed to the shaft 91. A pair of levers 111 are fixed to a rod 113, which is rotatably mounted between the side walls 13, and are provided with follower rolls 115 which ride along the peripheries of the cams 109. Rollers 117, having shafts 119 which extend through vertical slots 121 in the sleeves 75 and are xed to the conduits 73, are supported by and adapted to ride along the top surfaces of the levers 111.

The plate cams 93 and 109 are so designed and oriented on the shaft 95 as to cause the levers 111 to move downwardly through the arc as indicated at 123 and again return to their positions as shown in FIGURE 1 while the carriage 77 remains stationary at its position nearest to the bins 19. In this particular position of the carriage 77, the suction heads 71 will be disposed above a selected bin 19. Thus, during the downward movement of the levers 111 the rollers 117 also move downwardly causing their shafts 119 to lower the conduits 73 and the suction heads 71.

The arc of movement of the levers 111 is such as to permit the suction heads 71 to be lowered into the bottorn of the bins 19. However, the downward travel of the conduits 73 is variable and is arrested when the suction heads 71 contact the topmost sheet of the stack contained within a particular bin while the levers 111 continue their downward movement. As seen in FIGURE 2, the slots 27 formed in the front walls of the bins 19 facilitate unobstructed movement of the suction heads 71 as they are lowered into the bins.

To insure positive movement of the conduits 73, and thus snug engagement of the suction heads 71 with the topmost sheet in a bin 19, compression springs 125 are positioned between the bottoms of the sleeves 75 and collars 127 which are xed to the conduits. The lowermost ends of the conduits 73 are connected by flexible hoses 129 and 131 to a vacuum pump 133 which is operated by a switch 135.

In the operation of the above described apparatus, the pump 53 is actuated by the switch 55 until the elevator 23 raises a desired bin 19 approximately into alignment with the table 15. The switches 105 and 135 are then tripped to set the motor 97 and vacuum pump 133 into operation. During the initial rotation of the shaft 95, the carriage 77 is moved toward the bins 19 Where it remains stationary while the plate cams 109 cause the levers 111 to drop. As heretofore described, this movement of the levers 111 permits the suction heads 71 to engage with the topmost sheet in a bin and, in view, of the vacuum applied by the pump 133, hold onto the same.

The cams 109 now raise the levers 111 and suction heads 71 afterwhich the cams 93 cause the carriage 77 to be retracted into a position as shown in FIGURE l.

The sheet of wrapping material is still held by the suction heads 71 and, in this position of the carriage 77, the sheet is in easy reach of the article wrapping operator.

Where a series of sheets `are to be removed from a single bin, the motor 97 and vacuum pump 133 are preferably kept in constant operation. If necessary, suitable control means may be incorporated into the apparatus for controlling the speed of the shaft and thus regulating the delivery of the sheets.

I claim:

1. An article wrapping apparatus including a table at one end of which an article may be wrapped, a plurality of spaced bins for containing sheets of wrapping material positioned adjacent to the end of said table opposite to said one end thereof, means for moving said bins relative to said table for aligning a selected bin approximately with the plane thereof, a carriage, means located between the position of said plurality of bins and said one end of said table for guiding said carriage for horizontal movement toward and away from said bins, at least one suction head, means for applying a vacuum to said suction head, means supporting said suction head on said carriage for vertical reciprocating motion relative thereto, means including a cam for reciprocating said carriage along said guiding means to position said suction head alternately above said table and over a selected bin which is approximately aligned therewith, said cam being shaped to maintain said carriage stationary at the end of each stroke of its reciprocating movement, and means operative while said carriage is stationary and only when said suction head is positioned over a selected bin for reciprocating said suction head relative to said carriage, said last mentioned means including a spring for urging said suction head into the lowermost position of its reciprocating motion and into engagement with the topmost sheet in a selected bin and a cam for urging said suction head into its uppermost position of `its reciprocating motion.

References Cited UNITED STATES PATENTS 1,920,388 8/1933 Harrold 271-30 2,925,612 2/1960 Schramm 2l4-1 X 3,334,891 8/1967 Clausen et al 271-9 X FOREIGN PATENTS 301,529 10/1965 Netherlands. 939,740 10/ 1963 Great Britain.

EVON C. BLUNK, Primary Examiner.

R. J. HICKEY, Assistant Examiner.

U.S. Cl. X.R. 271-26, 42 

